The LCD of 7 and 20 is 140
140
140
20
The LCD of 3/20 and 7/30 is 60.
20
The least common denominator is 14. Whenever there are two values, and one is a multiple of the other, the multiple (larger number) is the LCD.
LCD of 7 and 37 is 259.
LCD(63, 7) = 63.
lcd(7, 97) = 679.
LCD(7, 4) = 28
LCD(7, 77) = 77
The LCD, or Lowest Common Denominator, is the smallest multiple of each of the denominators of a set of fractions. So, assuming that 2, 4 and 5 are denominators of fractions (1/2, 1/4 and 1/5, for example), the LCD would be 20, because 20 is the lowest number that 2, 4 and 5 multiply into. So, your new fractions would be 10/20, 5/20 and 4/20. The purpose of finding the LCD is to allow for multiplying fractions together, or simply comparing them easily.